subdosel

Subdosel is the forest layer beneath the canopy, encompassing the understory, shrub layer, and the regeneration zone where seedlings and saplings establish. The term is used in forest ecology to describe the vertical structure of forests and the ecological processes that occur below the tall trees. The depth and composition of the subdosel vary with forest type, disturbance history, and site productivity.

Environmental conditions in the subdosel are characterized by low light, cooler temperatures, higher humidity, and thicker leaf litter compared with the canopy. These factors favor shade-tolerant species and a diverse assemblage of plants such as shrubs, herbaceous plants, ferns, and mosses, along with juvenile trees that may eventually reach the canopy. In tropical forests the subdosel is often dense and species-rich; in temperate forests it may be sparser and dominated by deciduous or evergreen shrubs and saplings.

Fauna of the subdosel includes numerous insects, arachnids, amphibians, and birds that forage, seek shelter, or nest in the understorey. The microclimate and structure of the subdosel influence seed dispersal and predator–prey interactions, contributing to overall forest biodiversity.

Ecological roles include facilitating regeneration after disturbance, contributing to nutrient cycling through decomposing litter, and storing carbon in understory vegetation and soils. Gap formation, caused by tree death or breakage, creates bursts of light that temporarily alter subdosel conditions and drive successional change.

Researchers study the subdosel using field plots, microclimate measurements, and methods such as hemispherical photography or light sensors to estimate available light. Remote sensing and LiDAR increasingly help characterize vertical forest structure, including the subdosel, at larger scales.